Rotary kiln



March 17, 1931- L. s. PETERSEN ROTARY K ILN Filed Aug. 7. 1929 2 Sheets-Sheet l March 17, 1 3 L. s. PETERSEN ROTARY KILN Filed Aug. 7, 1929 2 Sheets-Sheet 2 anomto'c 9241M III! Patented Mar. 17, 1931 UNITED STATES PATENT OFFICE LOUIS STEFFEN PETERSEN, O1! ELIZABETH, NEW JERSEY, ASSIGNOR '10 1!. L. SMIDTH & (30., OF NEW YORK, N. Y., A CORPORATION OF NEW J'EBBEY ROTARY KILN Application flle d August 7, 1829. Serial No. 884,133.

This invention relates to rotary kilns and the like, in which the material acted upon is subjected to the action of the products of combustion or of heated air and in which A the transfer of heat to the material is promoted by the use of cross chains which are secured to the inner surface of the kiln or cylinder and in its rotation pass from the hot air or products of combustion through the material, which lies mainly in the lower part of the kiln or cylinder, thereby transferring heat to the material, and also pass from the material into the current of heated air or of products of combustion, lifting the material into the hot zone, thereby promoting the heating and drying of the material. The use of such chains is particularly desirable in the manufacture of Portland cement clinker in which the cement raw materials are introduced into the upper or feeding end of the kiln in the form of slurry from which the water must be driven off before the material reaches the calcining zone. In Letters Patent of the United States No. 1,313,281, dated August 18, 1919, issued to the assignee in the present case, there is shown and described an arran ement of such cross chains in the rotary kiln in which, in order to promote the forward movement of the slurry in the kiln, the chains are disposed helically. In the construction shown and described in said patent the kiln is shown without a lining of any sort. In the continued use of such kilns, it has been found that in order to secure the desired efiiciency the chain system must be very dense. Wear on the shell increases with the density of the chain system and in order to prevent excessive wear it has been found necessary to install a fire-brick lining, such a lining also conserving the heat of the gases or products of combustion. Because of the great heat in the interior of the kiln it has been found desirable to avoid as far as possible the exposure to such intense heat of the metallic devices by which the chains are secured, to the shell of the kiln, so that such devices shall not be destroyed by the heat and so release the chains and permit them to pass out other kiln with the clinker or of the material.

It has also been found desirable to secure such devices directly to the metal shell of the kiln, with as much area of contact as is practicable, so that the heat of the securing evices ma be conducted directly to the shell and issipated therefrom in the kiln room and the devices thus preserved against the destructive action of the intense heat. It is also desirable that such securin devices shall be as simple as possible an the bolts by which they are secured to the shell few in number so that the fastening devices may be removed readily in case of need. The present invention has been developed to meet these re uirements which have been experienced in t e use of the kiln shown in the patent above mentioned, the invention being particularly concerned with the devices by which the chains are secured to the shell and to the means by which such devices are protected as far as possible from the destructive action of the intense heat.

The invention will be more fully explained hereinafter with reference to the accompanying drawings in which it is illustrated, and in which:

Figure 1 is a view of Ion itudinal, sectional elevation of a kiln wit cross chains installed in accordance with the invention, the chains being indicated by broken lines and in much smaller number than would be used in practice in order to avoid confusion.

Figure 2 is a detail view in sectional elevation, the plane of section being indicated by the broken line 2-2 of Figure 1.

Figures 3 and 4 are detail views on a lar er scale, showing respectively in lan an side elevational views, as seen rom within the kiln, ortions of two chains and the devices by which the chains are secured to the shell of the kiln.

Figures 5 and 6 are views respectively similar to Figures 1 and 2, but showing the fastening devices arranged in longitudinal lines rather than in circumferential lines, as shown in Figures 1 and 2.

It will be understood that the kiln, of

as indicated in Figure 1.

which the metal shell is indicated at a, is disposed and supported for rotation in the usual manner.

In the embodiment of the invention illustrated in Figures 1 and 2 the kiln is shown as lined with segmental blocks 12 of fire-brick or other suitable lining material. These fire-brick se ments are in edge contact circumferentia 1y but spaced somewhat apart longitudinally in that portion of the kiln to which the chains are applied, so as to receive between them metal segmental bars a which are conformed closely to the inner surface of the shell 0;, so as to contact closely therewith, at least at their edges, as shown clearly in Figure 1. Each segmental bar is secured to the shell a by headed bolts a which receive nuts outside of the shell. Each bar is preferably channeled in a circumferential direction, on its inner face, but is provided on its flanges, at suitable intervals, with shoulders 0 adjacent which recesses c are formed, and on 1ts central body also at suitable intervals, with recessed cross ribs a, all for purposes to be explained. It will be observed that the segments a do not project inwardly beyond the lining segments 6.

The cross chains (1 are enga ed at their ,ends with yokes e the ends 0 which are received in, but spaced from rec a" in the cross ribs 0 and are secured in place by bolts 6, the heads of which enga .the shoulders or lugs c causing the b0 'es of the yokes to be clamped upon the shoulders with the bolts e extendlng therebetween. Oppositely extendin rojections e on the sides of the bodies 0 t e yokes' are received within the recesses o and prevent movement of the yokes in the planes thereof.

It will be observed that the yokes with their bolts e are the only parts of the devices, b which the chains are secured to the she I, which project inwardly beyond the lining and that the yokes themselves are in direct contact with the segments 0, which in turn are in direct contact with the metal shell a, so that the heat of the yokes is conducted directly to the metal shell whence it is dissipated in the kiln room. It will be understood that the ends of the yokes enter recesses formed in the cross ribs 0 and are thereby held from displacement in planes transverse to that of the yokes.

The chains d are arranged helieally, substantially as described in the patent above mentioned, and preferably are connected at their ends, as to each chain, to alternate circumferential lines of fastening devices,

It will be observed that the fastenin devices do not project beyond the inner %ace of the lining sufiiciently for any material effect in retarding the passage of the slurry or other material and that, as the chains han loosely from the yokes, but little heat will he lost to the chains by conduction through the fastening devices to the shell. It will also be noted that the removal and replacement of chains, when necessary, can be efiected with a minimum of time and labor. The lining segments, as will be noted, are held from movement by the metal bars which are bolted to the shell.

In the embodiment of the invention illustrated in Figures 5 and 6, the securin devices are arranged in longitudinal ines rather than in circumferential lines. The construction is substantially the same as shown in Figures 1 and 2, the lining'segments 6 being in contact longitudinally, end to end, but being spaced in a circumferential direction to receive between them longitudinal bars a of metal which are secured to the shell a of the kiln by bolts a, These bars are channeled longitudinally, both inwardly and outwardly, beari I at their outer edges as at 0, directly against the inner face of the shell a and having a plurality of lugs between their inner flBJFGS, as at c", to receive the bolts 6 and being ormed between their inner flanges with d cross ribs 0 to receive the ends of the yokes e. The chains d are arranged in substantially the same manner as shown in Figures 1 and 2.

It will be understood that other changes in details of construction and arrangement can be made to suit the convenience of the manufacturer or of the user and that the invention, except as pointed out in the accom an'ying claims, is not limited to the particu ar constructions shown and described herein.

I claim as my invention:

1. In a rotary kiln or the like, the combination of a metal shell, segmental lining blocks s aced a art and secured on the inner sur ace of t e shell, bars secured to the shell between the lining blocks, fastening devices secured to the bars, and chains enaged at their ends with the fastening evices.

2. In a rotary kiln or the like, the combination of a metal shell, segmental lining blocks spaced apart and secured on the inner surface of the shell, channeled bars secured to the shell between the lining blocks, fastening devices secured to the bars within the channels, and chains engaged at their ends with the fastening devices.

3. In a rotary kiln or the like, the combination of a metal shell, segmental lining blocks spaced apart and secured on the in- 3 okes having their ends received in recesses 1n the ribs, bolts engaged with the transverse ribs and with the yokes, and chains enga ed at their ends with the yokes.

4. in a rotary kiln or the like, the combination of a metal shell, segmental lining blocks spaced apartand secured on the inner surface of the shell, bars bolted to the shell between the lining blocks, fastening 10 devices secured to the bars, and chains enaged at their ends with the fastening evices.

5. In a rotary kiln or the like, the combination of a metal shell, segmental lining 15 blocks spaced apart longitudinally and secured to the inner surface of the shell, segmental bars secured to the shell between the lining blocks, fastening devices secured to the bars, and chains engaged at their ends 20 with the fastening devices of alternate segmental bars.

This specification signed this 6th day of August, A. D. 1929.

LOUIS S. PETERSEN.

yokes having their ends received in recesses 1n the ribs, bolts engaged with the transverse ribs and with the yokes, and chains engaged at their ends with the yokes.

4. In a rotary kiln or the like, the combination of a metal shell, segmental lining blocks spaced apart-and secured on the inner surface of the shell, bars bolted to the shell between the lining blocks, fastening devices secured to the bars, and chains engaged at their ends with the fastening devices.

5. In a rotary kiln or the like, the combination of a metal shell, se mental lining blocks spaced apart longitu inally and secured to the inner surface of the shell, segmental bars secured to the shell between the lining blocks, fastening devices secured to the bars, and chains engaged at their ends with the fastening devices of alternate segmental bars.

This specification signed this 6th day of August, A. D. 1929.

LOUIS S. PETERSEN.

CERTIFICATE OF CORRECTION.

Patent No. 1,796,664. Granted March 17, 1931, to

LOUIS STEFFEN PETERSEN.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1, lines 51 and 52, strike out the words "other kiln with the clinker or of the material" and insert instead of the kiln with the clinker or other material; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 5th day of May, A. D. 1931.

M J. Moore,

(Seal) Acting Commissioner of Patents.

CERTIFICATE OF CORRECTION.

Patent No. 1,796,664. Granted March 17, 1931, to

LOUIS STEFFEN PETERSEN.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1, lines 5] and 52, strike out the words "other kiln with the clinker or of the material" and insert instead of the kiln with the clinker or other material; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 5th day of May, A. D. 1931.

M. J. Moore, Acting Commissioner of Patents. 

